Angioplasty device

ABSTRACT

The invention relates to an angioplasty device for treating stenoses or occlusions that facilitates the diagnosis and visualization of the stenosis and the treatment control having a duct dedicated to the injection of the contrast product.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/130,022 filed May 18, 2011 which is a 371 of PCT/FR2009/001326 filedon Nov. 18, 2009, published on May 27, 2010 under publication number WO2010/058103 A, and claims priority benefits to French patent applicationnumber 08 06472 filed Nov. 19, 2008 the entire disclosures of which areincorporated herein by reference.

TECHNICAL FIELD OF THE INVENTION

The invention relates to an angioplasty device to be introduced into aconduit of the human body, which conduit is preferably a blood vessel,so as to permit the local widening of the conduit. This device isparticularly useful for treating occlusions or stenoses of the bloodvessels.

PRIOR ART

To treat a stenosis or an occlusion of a blood vessel, an angioplastydevice can be used that is composed of a rod on which an inflatableballoon is fixed. Such a device is described in EP 1 897 584, forexample. This device comprises a rod which is provided with aninflatable balloon and in which two conduits are formed. The firstconduit is designed to receive a flexible guide wire for guiding thepath of the device in the vessel as far as the zone that is to betreated, while the second conduit is in fluidic communication with theballoon, thus permitting the injection of a pressurized fluid into theballoon, in this particular case physiological saline, if appropriatemixed with an iodine contrast agent.

To fit this device in place, a contrast agent can be injected into theblood vessel in order to locate the stenosis. A guide wire is thenintroduced into the vessel to be treated in order to make it easier tointroduce the angioplasty device into the area of the stenosis. A guidewire and a method for using it are described in the document FR 2 533130, for example.

The angioplasty device is then introduced around the guide wire in sucha way that the guide wire is located in the first conduit. Once theballoon has been introduced into the area of the stenosis, a pressurizedfluid is injected into the balloon with the aid of the second conduit.The inflation of the balloon makes it possible to widen the blood vesselin the area of the stenosis. It is then once again necessary tovisualize the blood vessel in order to check that the stenosis hasindeed been rectified. To do this, the balloon catheter is withdrawn andreplaced by an angiography catheter which has a multi-perforate end andwhich is positioned in line with or upstream from the treated lesion.The guide is then withdrawn and an iodine contrast agent is injectedinto the lumen of the angiography catheter. If a new angioplasty isrequired, the guide can be mounted again on the angiography catheter,and the catheter can then be withdrawn and replaced by the ballooncatheter.

Alternatively, to make matters simpler, the guide wire can be withdrawnand the contrast agent can be injected though the lumen freed by theguide wire, as long as the diameter of this guide lumen is sufficient,given that the contrast agent is viscous. In cases where the stenosishas not been totally rectified, the balloon has to be repositioned atthe location where the blood vessel is narrowed. To do this, a guidewire must be re-introduced into the first conduit in order to permit therepositioning of the balloon in the narrowed area of the blood vessel.This maneuver of repositioning the balloon can be repeated several timesif the stenosis has not been completely rectified.

Thus, the treatment of a stenosis, or of an occlusion, involves asuccession of treatment phases, during which the balloon is inflated,and of visualization phases, during which a contrast agent is injected.Between each treatment phase and visualization phase, the operatorperforming the injection must either withdraw the balloon and replace itby an angiography catheter or must withdraw the guide wire in order touse the freed channel. This successive introduction and withdrawal ofthe guide wire into and out of the first conduit is time-consuming andawkward for the surgeon to do.

Another disadvantage of these techniques is that the distribution of thecontrast agent in the blood vessel always takes place in the directionof flow of the blood, with the result that if the vessel comprisesbranches between the injection point and the location of the lesion,some of the contrast agent is uselessly diffused into the adjoiningvessels.

In addition, in the devices of the prior art, the contrast agent isinjected into the blood vessel with the aid of the first conduit, suchthat it is injected into the whole of the blood vessel. Large amounts ofcontrast agent are therefore injected into the patient's blood, and thiscan have adverse consequences for the health of the patient.

DISCLOSURE OF THE INVENTION

It is an object of the invention to overcome the disadvantages of theprior art by making available a percutaneous transluminal angioplastydevice with which it is possible to visualize the blood vessel withouthaving to perform any additional maneuver. It is also an object of theinvention to improve the quality of visualization while at the same timereducing the amounts of contrast agent that are injected into thepatient's blood.

To this end, a first aspect of the invention concerns an angioplastydevice comprising:

-   -   a guide wire to be inserted into a blood vessel,    -   a flexible tubular body extending along a longitudinal axis        between a proximal end and a distal end and having a proximal        part, which includes the proximal end, and a distal part, which        includes the distal end, the tubular body comprising:        -   an inflatable balloon arranged radially about the tubular            body in the distal part;        -   a first leaktight internal conduit extending parallel to the            longitudinal axis at least in the distal part, so as to            permit the insertion of the guide wire into the first            conduit and the sliding of the tubular body along the guide            wire;        -   at least a second internal conduit extending parallel to the            longitudinal axis and opening out, on the one hand, at the            proximal end and, on the other hand, into the balloon (5),            in such a way as to permit the injection of a fluid into the            balloon;            in which angioplasty device the tubular body additionally            comprises:    -   one or more injection orifices situated in the distal part;    -   a third internal conduit opening out, on the one hand, at the        proximal end and, on the other hand, into the injection orifice        or orifices, in such a way as to permit the injection of a        contrast agent through the one or more injection orifices when        the guide wire is in the first conduit.

The angioplasty device thus comprises a third conduit and at least oneinfusion orifice situated in the distal part of the tubular body. Thisinjection orifice permits the injection of a contrast agent into theblood without the need to withdraw the guide wire. The angioplastydevice can therefore be repositioned very easily and very quickly. Theinjection orifice is preferably located less than 5 cm from the balloon.In cases where the tubular body comprises several injection orifices,the injection orifice farthest from the balloon is preferably locatedless than 5 cm from the balloon.

This device can therefore be used for the diagnosis of stenoses orocclusions, and it can also be used for their treatment. This devicealso makes it possible to check that the inflating of the balloon hasindeed rectified the occlusion or the stenosis, without the need toremove the guide wire.

This device therefore serves as a visualization probe and, at the sametime, as an instrument for treating the stenoses or occlusions.

Moreover, the contrast agent is injected locally by virtue of theinfusion orifice situated in proximity to the balloon, which permitsvery precise visualization of the area of interest through injecting asmall amount of contrast agent into the patient's blood.

The quality of visualization of the contrast agent can also be improvedby distributing infusion orifices radially about the tubular body,downstream and upstream from the balloon, by which means it is possibleto obtain a satisfactory distribution of the contrast agent,irrespective of the direction of flow of the blood.

The second conduit is leaktight in order to ensure that the fluid forinflating the balloon does not enter the patient's blood.

Advantageously, according to one embodiment, the first conduit iscircular and has a diameter substantially equal to that of the guidewire. In this way, the conduit and the guide wire are in good contactand, by this means, the angioplasty device is more easily guided by theguide wire.

According to another embodiment, the first conduit is open radially onthe third conduit in order to form a single conduit, the diameter of thesingle conduit being greater than the external diameter of the guidewire in the proximal part of the tubular body, the diameter of thesingle conduit being substantially equal to the external diameter of theguide wire in the distal end of the tubular body. In this embodiment,the infusion orifices are preferably situated upstream from the portionof the single conduit whose diameter is substantially equal to that ofthe guide wire, such that the contrast agent can be injected without theneed to withdraw the guide wire, since the contrast agent exits throughthe infusion orifices that are situated upstream from the conduitportion that is narrower. This embodiment also allows the contrast agentto be injected at high pressure by withdrawing the guide from the distalpart in such a way as to obtain a supplementary injection orifice.Moreover, during the passage of the tubular body around the guide wire,friction is minimized. This embodiment is also advantageous in terms ofindustrial production of the tubular body, since only two conduits haveto be formed in the tubular body, instead of the three conduits presentin the preceding embodiments.

The cross section of the third conduit must be chosen in such a way asto satisfy two contradictory conditions: it must be as large as possiblein order to permit a rapid rate of injection of the contrast agent, ofwhich the viscosity is high, and it must also be small enough to ensurethat the device as a whole has the smallest possible diameter.

According to different embodiments:

-   -   each conduit can be leaktight, in order to control the flow of        the fluids in the device;    -   the tubular body can comprise a plurality of injection orifices        in fluidic communication with the third conduit, the injection        orifices being distributed radially about the tubular body; this        distribution of the injection orifices permits a better        distribution of the visualization medium in the area to be        treated;    -   the one or more injection orifices include at least one        downstream injection orifice situated downstream from the        balloon;    -   the one or more injection orifices include at least one upstream        injection orifice situated upstream from the balloon; the        distribution of the injection orifices upstream and downstream        from the balloon makes it possible to improve the visualization        of the stenosis, irrespective of the direction of flow of the        blood;    -   the first, second and third conduits can be concentric; in this        case, the first conduit is at the center in order to provide a        good hold of the guide wire, the second conduit surrounds the        first conduit, and the third conduit surrounds the first and        second conduits in order to permit better visualization of the        area in which the balloon is situated; this arrangement can save        space, such that the diameter of the tubular body as a whole is        reduced and, as a result, the insertion of the angioplasty        device into the blood is easier;    -   the first, second and third conduits are arranged side by side,        which makes production of the device easier;    -   the proximal end of the tubular body is provided with three        connector pieces, each connector piece being attached in a        leaktight manner to one of the conduits;    -   the first conduit is open radially on the third conduit, which        reduces the number of conduits to be formed and makes them        easier to produce, especially when the conduits are produced by        drilling the tubular body;    -   the first conduit opens out, on the one hand, at the proximal        end and, on the other hand, at the distal end, which allows the        guide wire to pass from one end to the other;    -   the first conduit opens out, on the one hand, at an intermediate        position between the proximal end and the distal end and, on the        other hand, at the distal end, which facilitates the        manipulations between the tubular body and the guide wire.

The invention also relates to a tubular body according to one of theembodiments described above.

BRIEF DESCRIPTION OF THE FIGURES

Other features and advantages of the invention will become clear fromthe following description and by reference to the attached figures, inwhich:

FIG. 1 shows a schematic view of an angioplasty device according to afirst embodiment of the invention;

FIG. 2 shows a cross-sectional view of the tubular body of theangioplasty device from FIG. 1;

FIG. 3 shows a cross-sectional view of the tubular body of anangioplasty device according to a second embodiment of the invention;

FIG. 4 shows a cross-sectional view of the tubular body of anangioplasty device according to a third embodiment of the invention;

FIG. 5 shows a cross-sectional view of the tubular body of anangioplasty device according to a fourth embodiment of the invention;

FIG. 6 shows a cross-sectional view of the tubular body of anangioplasty device according to a fifth embodiment of the invention;

FIG. 7 shows a cross-sectional view of the tubular body of anangioplasty device according to a sixth embodiment of the invention;

FIG. 8 shows a schematic view of an angioplasty device according to aseventh embodiment of the invention;

FIG. 9 shows a schematic view of an angioplasty device according to aneighth embodiment of the invention;

FIG. 10 shows a cross-sectional view of the proximal part of theangioplasty device from FIG. 9;

FIG. 11 shows a cross-sectional view of the end of the distal part ofthe angioplasty device from FIG. 9;

FIG. 12 shows a cross-sectional view of the proximal part of a ninthembodiment of the invention;

FIG. 13 shows a schematic view of an angioplasty device according to asecond embodiment.

For greater clarity, identical or similar elements are designated byidentical reference signs in all of the figures.

DETAILED DESCRIPTION OF AN EMBODIMENT

The angioplasty device shown in FIG. 1 comprises a tubular body 1 madeof a flexible and biocompatible material, especially a syntheticmaterial, and extending along a longitudinal axis 2 between a proximalend 3 and a distal end 4. The tubular body additionally comprises aproximal part 3A, which includes the proximal end 3, and a distal part4A, which includes the distal end 4. The tubular body 1 is provided, inits distal part 4A, with an inflatable balloon 5, which radiallysurrounds the tubular body.

The tubular body 1 additionally comprises injection orifices 12, whichare formed in the wall of the tubular body and which are arrangedradially upstream 12B and downstream 12A from the inflatable balloon 5.These injection orifices 12 are arranged in proximity to the inflatableballoon. The terms upstream and downstream refer to the direction offlow of the fluid in the angioplasty device.

Three conduits 6, 7, 8, which are shown in section in FIG. 2, passthrough the tubular body. The three conduits 6, 7 and 8 extend parallelto the longitudinal axis. The first conduit 6 extends along the entirelength of the tubular body, such that it connects the distal andproximal ends 3, 4 of the tubular body. The first conduit 6 is ofcircular cross section and has an internal diameter substantially equalto the external diameter of the guide wire that will allow theangioplasty device to be placed in the vein. Thus, the angioplastydevice is better guided by the guide wire. The proximal end 3 isadditionally provided with a connector piece 9, which is attached to thefirst conduit 6. The guide wire is introduced into the first conduit 6through the connector piece 9.

The second conduit 7 connects the proximal end 3 of the tubular body tothe inflatable balloon 5 in a leaktight manner. The proximal end 3 isprovided with a second connector piece 10, which is attached in aleaktight manner to the second conduit. The connector piece 10 isdesigned to be attached to a device for injecting a pressurized fluidinto the second conduit 7 in order to inflate the balloon. Thispressurized fluid is advantageously a mixture of physiological salineand contrast agent.

The third conduit 8 connects the proximal end 3 of the tubular body tothe infusion orifices 12. The proximal end 3 is additionally providedwith a third connector piece 11, which is connected in a leaktightmanner to the third conduit 8. The third conduit 8 permits the injectionof a contrast agent into the blood vessel in order to visualize thenarrowing of the blood vessel to be treated and in order to monitor thelatter after the angioplasty.

Moreover, to make it easier to position the balloon at the location ofthe narrowing, in particular when the balloon is not inflated, apositioning ring 13 is placed in the balloon. This positioning ring 13is detectable, just like the contrast agent, by X-ray. In a preferredembodiment, the tubular body can comprise two positioning rings, each ofthese rings being placed at the limit of the balloon so as to permitdetection of the latter.

The arrangement of the conduits inside the tubular body can vary, as canbe seen in FIGS. 3 to 7. In FIGS. 3 and 4, the first conduit 6 has acircular cross section with a diameter substantially equal to that ofthe guide wire that will be introduced into this first conduit 6. In thearrangement in FIG. 3, the second and third conduits 7 and 8 arearranged as crescents around the first conduit, whereas in thearrangement in FIG. 4 the three conduits 6, 7 and 8 are of circularcross section and are concentric. The first conduit 6 is at the centerof the tubular body and is surrounded by the second conduit 7, which isitself surrounded by the third conduit 8.

FIGS. 5 to 7 show another arrangement in which the first conduit 6 isopen radially on the third conduit 8. In these embodiments, the firstconduit still has a circular cross section with a diameter substantiallyequal to that of the guide wire so as to permit efficient guiding of thetubular body around the guide wire. To save space and reduce the numberof holes to be made, the first conduit 6 is open radially on the thirdconduit 8. In FIG. 5, the third conduit is in fact composed of threeconduits 8 a, 8 b, 8 c, which communicate with the first conduit and aredistributed radially about the first conduit. This arrangement isparticularly advantageous when the infusion orifices 12 are distributedradially about the tubular body, since it permits a good distribution ofthe infusion product between the infusion orifices 12. Likewise in FIG.7, the third conduit is in fact composed of four conduits 8 a, 8 b, 8 c,8 d, which communicate with the first conduit and are distributedradially about the first conduit. These embodiments additionally allowthe third conduit to be dimensioned according to the amount of contrastagent to be injected, but also according to the viscosity thereof.

FIG. 8 shows an angioplasty device according to another embodiment ofthe invention. In this embodiment, the tubular body 1 comprises only twoconduits in its proximal part 3A, namely the second and third conduits,and it comprises three conduits in its distal part 4A. In this partwhere the tubular body comprises only two conduits, the guide wire 14 isexternal to the tubular body 1, whereas in the distal part, where thetubular body comprises three conduits, the guide wire passes through thefirst conduit.

FIGS. 9, 10 and 11 show an angioplasty device according to anotherembodiment, in which the first conduit 6 and the third conduit 8 aremerged and form a single conduit 68. This single conduit 68 has adiameter greater than the external diameter of the guide wire 14 alongthe entire length of the tubular body, except for the end of the distalpart 4, where the single conduit has a diameter substantially equal tothe external diameter of the guide wire 14. A cross section of theproximal part of the tubular body of this angioplasty device is shown inFIG. 10, and a cross section of the end of the distal part of thetubular body of this angioplasty device is shown in FIG. 11. The secondconduit 7 and the single conduit 68 are concentric in this embodiment.The infusion orifices 12 are preferably situated upstream from theportion of the single conduit 68 whose diameter is equal to that of thetubular body, so as to make it easier for the contrast agent to passthrough the single conduit 68, without having to withdraw the guidewire. This arrangement permits the injection of a pressurized contrastagent. In addition, it reduces the friction between the guide wire 14and the conical conduit 68.

FIG. 12 shows a variant of the embodiment from FIG. 9, in which variantthe single conduit 68 and the second conduit are not concentric.

FIG. 13 shows a variant of the embodiment from FIG. 9. In thisembodiment, the first conduit 6 and the third conduit 8 are merged andform a single conduit 68. This single conduit 68 has a diameter greaterthan the external diameter of the guide wire 14 along the entire lengthof the tubular body, except for the distal part 4A, where the singleconduit 68 has a diameter substantially equal to the external diameterof the guide wire 14 in the distal part 4A of the tubular body. Inaddition, in this embodiment, the balloon 5 is positioned at the distalend 4A of the tubular body, around the part of the single conduit 68having a diameter substantially equal to the diameter of the guide wire14. In this way, the tubular body has substantially the same diameteralong its entire length. In addition, this diameter is relatively small.

The treatment of a stenosis with the aid of the angioplasty device inFIG. 1 will now be described.

In a first step, the operator inserts a catheter into the vein to betreated and injects a contrast agent, for example iodine, into the bloodvessel to be treated. By virtue of this contrast agent, the operator canobserve the blood vessel by radiography and is thus able to locate thestenosis that is to be treated. The operator then introduces the guidewire into the vessel to be treated and thereafter inserts theangioplasty device into the blood vessel by sliding the first conduitover the guide wire. The guide wire facilitates the introduction of theangioplasty device despite the flexibility and the length of the latter.

The operator places the balloon in the area of the narrowing with theaid of the marker ring 13, which is radiolabeled. Once the balloon hasreached the narrowed segment of the blood vessel, the operator inflatesthe balloon with the aid of the second conduit 7. The atheromatousdeposits narrowing the vessel are then compressed against the walls ofthe blood vessel, thereby permitting an increase in the diameter of theinternal lumen of the vessel. Once this maneuver has been performed, theballoon is deflated, again with the aid of the second conduit 7.

Then, with the aid of the third conduit, the operator injects a contrastagent into the patient's blood without having to carry out themanipulations necessary in the prior art. The injection of this contrastagent allows the operator to visualize the blood vessel after theinflation of the balloon, so as to be able to check that the narrowedsegment has indeed been rectified. In cases where this narrowed segmenthas not been totally rectified by the first inflation, the operator canmove the balloon in order to reposition it in the area of the remainingnarrowed portion. This remaining narrowed portion is detected with theaid of the contrast agent. Once the balloon has been repositioned, theoperator can re-inflate the balloon. He can then once again checkwhether this maneuver has been successful. The operator can repeat thesewidening/checking maneuvers as many times as is necessary and can do sowithout having to carry out any additional manipulation, which saves himconsiderable time and avoids possible incidents during the manipulation.In addition, the contrast agent is injected locally, by which means thepractitioner is able to clearly visualize the area of interest withoutexcessive contrast agent having to be injected into the patient's blood.

Of course, the invention is not limited to the above illustrativeembodiments, and various modifications or variations can be envisioned.For example, other arrangements of the three conduits can be envisioned.It is also conceivable to add a fourth conduit in the tubular body, forexample for injecting medicaments or active substances into the blood.

Moreover, the tubular body can either be a solid cylinder in which threeconduits are drilled or can be in the form of a cylindrical outer wallwhich surrounds the three conduits.

The invention claimed is:
 1. An angioplasty device for local widening ofa narrowed segment of an internal lumen of a blood vessel includingatheromatous deposits on walls of the blood vessel, comprising: a guidewire insertable into a blood vessel, a flexible tubular body extendingalong a longitudinal axis between a proximal end and a distal end andhaving a proximal part, which includes the proximal end, and a distalpart, which includes the distal end, the tubular body comprising: aninflatable angioplasty balloon arranged radially about the tubular bodyin the distal part, wherein the angioplasty balloon is such that aninflation of the angioplasty balloon in the narrowed segment of theblood vessel results in the internal lumen of the blood vessel beingwidened and the atheromatous deposits being compressed against the wallsof the blood vessel; a first internal conduit extending parallel to thelongitudinal axis at least in the distal part, to enable the insertionof the guide wire into the first conduit and the sliding of the tubularbody along the guide wire; a second internal conduit extending parallelto the longitudinal axis and opening out at the proximal end and intothe angioplasty balloon, to enable the injection of a fluid into theangioplasty balloon to inflate the angioplasty balloon; a third internalconduit opening out at the proximal end and into several injectionorifices situated in the distal part, the first conduit being openradially into the third conduit, the second conduit being leaktight withrespect to the first and third conduits, the third conduit having across-section dimension based on an amount and viscosity of a contrastagent to be injected therethrough in a patient's blood when the guidewire is in the first conduit.
 2. The angioplasty device of claim 1,wherein the injection orifices are distributed radially about thetubular body.
 3. The angioplasty device of claim 1, wherein theinjection orifices include at least one downstream injection orificesituated downstream with respect to the patient's blood flow from theangioplasty balloon.
 4. The angioplasty device of claim 1, wherein theinjection orifices include at least one upstream injection orificesituated upstream with respect to the patient's blood flow from theangioplasty balloon.
 5. The angioplasty device of claim 1, wherein thefirst, second and third conduits are concentric.
 6. The angioplastydevice of claim 1, wherein the first, second and third conduits arearranged side by side.
 7. The angioplasty device of claim 1, wherein thefirst conduit is of circular cross section and has a diametersubstantially equal to that of the guide wire.
 8. The angioplasty deviceof claim 1, wherein the proximal end of the device is provided withthree connector pieces each connector piece being attached in aleaktight manner to one of the conduits.
 9. The angioplasty device ofclaim 1, wherein the first conduit opens out at the proximal end and atthe distal end.
 10. The angioplasty device of claim 1, wherein the firstconduit opens out at an intermediate position between the proximal endand the distal end and at the distal end.